i have this and i do not respond well to it, so just a warning. many people like it but it made me jittery and unable to rest. with weak adrenals i think i respond differently to certain things. my husband used it and rested well, but can't use it as it gives him loose bowels. i am wary of magnesium supplements in general as one mineral should never be taken alone, only in a combination with other minerals as it upsets the mineral balance of the body. prolonged use of just one will (unless you are extremely deficient) upset your overall balance. i take minerals in herbal form so i know i am getting a perfect balance, plus they are easily absorbed. whatever the body does not use is passed and no harm is done when taken as a food source. taking too much magnesium night aftrer night will upset your calcium balance. the best food source or herb out there to get all your minerals from is kelp. just make sure it is from a reputable company.